A STUDY OF COLONIES OF THE KITTIWAKE RISSA TRIDACTYLA (L.)

• Published in: Ibis
• Main Authors: Coulson, J. C., White, E.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1956
• Subjects: Marsden; rissa tridactyla
• Online Access: http://dx.doi.org/10.1111/j.1474-919x.1956.tb03030.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1474-919X.1956.tb03030.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1474-919X.1956.tb03030.x

Summary. The history of Kittiwake colonics at Marsden, Co. Durham and North Shields, Northumberland is given. Since the original colonization of the area in 1930, nine colonies have been formed which, in 1954, ranged in size from 13 to 648 nests. New colonies were formed by birds being present on the site a year before breeding commenced. Immigration continued for at least the first four years of a colony's existence. Colour‐ringing showed that adult Kittiwakes exhibited both colony‐and site‐tenacity. A large proportion of non‐breeding birds was present, higher in the younger colonies. These birds returned to the colonies later than the breeding birds and the majority were young birds returning for the first time. In 1953 at least 19% of the population in the area were non‐breeding birds. Colony age and colony size were closely correlated. The return to the colonies and onset of breeding within the colonies occurred first in the oldest and last in the youngest colonies. Birds of the same age bred at the same time irrespective of colony size. Furhter, the spread of breeding within large colonies was greater than in small ones, whereas the reverse would have been expected if “social stimulation” was of major importance. It is conducted that the age of birds within a colony is more important than “social stimulation” in influencing the time of breeding.